摘要:
Die Erfindung beschreibt ein Verfahren zum Nachführen zweier Kommunikationsteilnehmer eines optischen Satelliten-Kommunikationssystems, insbesondere eines Satelliten und einer Bodenstation, zur Bereitstellung einer optischen Kommunikationsverbindung zwischen den zwei Kommunikationsteilnehmem. In dem erfindungsgemäßen Verfahren überträgt ein erster der beiden Kommunikationsteilnehmer ein optisches Signal (15) an einen zweiten der beiden Kommunikationsteilnehmer. Der zweite Kommunikationsteilnehmer umfasst eine Detektoranordnung mit mehreren Detektoren (12, 13, 19) in einer gemeinsamen Empfangsebene (22), durch die jeweils die Phase des Signals (15) erfasst wird, wobei durch ein Phasenverarbeitungsmittel Phasendifferenzen zwischen den Phasen des Signals ermittelt werden. Aus den Phasendifferenzen wird ein Fehlwinkel (18) der Ausrichtung des Signals zu der Empfangsebene ermittelt. Der Fehlwinkel (18) wird durch einen Nachführrechner verarbeitet, um die Empfangseinheit des jeweiligen Kommunikationsteilnehmers auf das Signal auszurichten, so dass die Phasendifferenzen Null ergeben. Dabei werden die Detektoren (12, 13, 19) kontinuierlich kalibriert.
摘要:
A method and system are provided for calibrating on-board aviation equipment. An actual bearing from an aircraft to an automatic direction finder (ADF) station is determined. The aircraft is moved to a plurality of headings. An ADF bearing is determined from the aircraft to the ADF station at each of the plurality of headings. An error between the actual bearing and the ADF bearing at each heading is calculated. Then, an error function as a function of the heading of the aircraft is generated based at least in part on the calculated error.
摘要:
A system determines bearing for situational awareness. The system may include a receiver, a processor, and a memory comprising an engine for performing a method. The method includes receiving signals using directional reception; receiving positional data; calculating a correction amount; and applying the correction amount to subsequent uncorrected bearings to provide corrected bearings. Positional data may be received in any conventional format including data link, ADS-B, and MODE S. Positional data may be determined in the target using a global positioning system. The system may provide a signal to display the corrected bearing and/or provide traffic alerting and collision avoidance advisories.
摘要:
A digitizer arrangement for converting an analogue signal into a digital signal, including a first A/D converter, said first A/D converter being arranged to convert said analogue signal into a first digital signal with a first sampling rate, the first sampling rate being lower than the frequency of the analogue signal, a second A/D converter, said second A/D converter being arranged to convert said high frequency analogue signal into a second digital signal with a second sampling rate, the second sampling rate being lower than the frequency of the analogue signal, means for combining said first and second digital signals into a third digital signal with a third sampling rate that is at least a multiple of said first and second sampling rates.
摘要:
Die Erfindung bezieht sich auf eine Vorrichtung zur Erkennung der Betriebsart Senden eines Lawinenverschütteten-Suchgerätes, welches sich in der unmittelbaren Umgebung der Vorrichtung befindet. Die Vorrichtung besteht aus mindetens einer Antenne, mindestens einem Empfänger und nachgeschalteten Mitteln zur Auswertung der empfangenen Signale und zur Entscheidung über die Veränderung des Zustandes eines Signalisationsmittels. Die Signale von mehreren Antennen werden auf geeignete Weise gemessen und kombiniert, bevor sie zur Entscheidung über die Veränderung des Zustandes des Signalisationsmittels beigezogen werden. Die Schwellwerte der Kriterien für die Entscheidung sind einstellbar.
摘要:
The invention provides a method and apparatus for determining the direction of a signal such as for example a received radio signal in a cellular mobile communication system. At lest two antenna arrays (10, 12) are connected to associated processors (14, 16) for extracting the desired signal and two independent direction of arrival estimates are determined in associated direction estimators (18, 20). A similarity testing unit (22) determines the direction of arrival and the accuracy of this estimate from the difference between the two estimates. A feature of the invention is controlling the beam form of a downlink signal in response to the direction estimate and the determined accuracy.
摘要:
The invention relates to radar and can be used in radar posts using the phase method of measuring the angular co-ordinates of moving objects for guidance systems which use calculations of target positional data. The proposed system comprises the following elements: a multichannel receiving antenna-feed system and frequency converter; back-up and measurement channel receivers; a calibration signal circuit; a signal processor; a Doppler frequency synthesiser; (connected in series to the output of the back-up channel receiver) a multichannel Doppler frequency filter, detector and meter; (connected in series to the output of the multichannel Doppler frequency filter) a multiplexer, a heterodyne frequency converter whose second input is connected to the heterodyne output, a power divider, a second mixer whose signal input is connected to the first output of the frequency converter, a band-pass filter, an amplifier, and a phase meter. The second output from the power divider is connected to the heterodyne input of the first mixer of the measurement channel receiver whose output is connected to the second input of the phase meter; the output of the Doppler frequency synthesiser is connected via a switch to the control input of the controlled attenuating circuit whose signal input is connected to the passive divider, while its output is connected via the calibration signal circuit to the communications unit of the receiving antenna-feed device and calibration signal circuit.
摘要:
A hybrid amplitude/phase comparison direction finding system for aircraft, employing a unique calibration system to compensate for tolerance variations in the antennas. The calibration system utilizes a programmable read only memory (PROM) (34) for each antenna pair (30), wherein calibration data from pre-measured antenna patterns of the associated antennas are stored. The calibration data preferably includes measured relative amplitude (electromagnetic field strength) and phase data (46), as a function of frequency and angle from a common reference plane, for the associated antenna pair. This calibration data is stored in a PROM which is preferably disposed within an assembly which includes the antenna pair. A system processor (45) can then retrieve the calibration data during system operation, whereupon angle of arrival measurements can be performed with improved accuracy.
摘要:
A hybrid amplitude/phase comparison direction finding system for aircraft, employing a unique calibration system to compensate for tolerance variations in the antennas. The calibration system utilizes a programmable read only memory (PROM) (34) for each antenna pair (30), wherein calibration data from pre-measured antenna patterns of the associated antennas are stored. The calibration data preferably includes measured relative amplitude (electromagnetic field strength) and phase data (46), as a function of frequency and angle from a common reference plane, for the associated antenna pair. This calibration data is stored in a PROM which is preferably disposed within an assembly which includes the antenna pair. A system processor (45) can then retrieve the calibration data during system operation, whereupon angle of arrival measurements can be performed with improved accuracy.